The study of more than 300 women who underwent breast radiation found that almost half had heard "frightening" stories going into treatment. But only 2 percent ultimately agreed that the stories were true.

And over 80 percent of all patients said their experience with radiation therapy was actually "less scary" than they'd expected.

Researchers said the findings show that the public still has misconceptions about "modern" radiation therapy.

But over the past 20 years, there have been key advances in how breast radiation is given, explained McCloskey, an assistant professor of radiation oncology at the University of California, Los Angeles.

It's more precise and shorter in duration -- which has helped limit short-term side effects like skin burning and breast pain.

Doctors can also now create individualized radiation plans for each patient, and give the treatment in "more convenient" schedules, McCloskey noted.

Dr. Beryl McCormick is a radiation oncologist at Memorial Sloan Kettering Cancer Center in New York City.

She said that in her experience, it's "extremely common" for patients to go into treatment having heard scary stories.

The side effects of any cancer treatment will vary from one person to another. But McCormick said it's possible to predict what women can typically expect.

For example, skin symptoms vary based on whether a woman had only the breast tumor removed (a lumpectomy), or breast-removal surgery (a mastectomy).

With lumpectomy patients, McCormick said she usually tells them the skin effects will be similar to what would happen if they were out in the sun for two hours without sunscreen.

Those skin symptoms typically go away a few weeks after treatment ends, she noted.

With mastectomy patients, the effects would typically be more pronounced and lasting, because the radiation therapy is actually, in part, targeting the skin, McCormick said.

What's important, she added, is that women have a thorough discussion of the benefits and risks of radiation therapy when making treatment decisions.

"That discussion should start with their surgeon, who is usually the first [doctor] a woman will see," McCormick said.

If a woman finds the surgeon cannot answer all her questions, she can ask to talk to a radiation oncologist, McCormick suggested.

The study findings were based on 327 women who'd been treated for breast cancer within the past several years. They'd had surgery, followed by radiation -- usually a lumpectomy, though 17 percent had undergone a mastectomy.

Overall, 47 percent said that before starting treatment, they'd read or heard "scary" stories about the effects of breast radiation. And many went into treatment worried about risks like skin burning and damage to the internal organs.

In hindsight, though, few women felt their experience matched the stories they'd heard.

Instead, 84 percent said their side effects -- including skin symptoms, pain and fatigue -- had been less serious than they'd expected. Similar percentages also said their treatment had been less disruptive to their work and family life than they'd feared.

The long-term outlook was better than most women had thought, too. Of women who'd gotten a lumpectomy, 89 percent said the appearance of their irradiated breast was better than they'd expected.

Similarly, 67 percent of mastectomy patients said the appearance of the radiation-treated area was better than they'd anticipated, according to the report.

Finally, the vast majority of women agreed with the statement, "If future patients knew the real truth about radiation therapy, they would be less scared about treatment."

The study was published Feb. 26 in the journal Cancer.

McCloskey said she hopes the findings will offer future patients a "better idea of the breast radiation experience when making treatment decisions."

McCormick agreed. "Almost everyone in the study went through [radiation] therapy and said it wasn't as scary as they'd thought," she said. "I think that's pretty powerful."

In the longer term, chest radiation carries a risk of heart or lung disease, since it can damage those organs. But recent research shows that among nonsmoking women who receive breast radiation, less than 1 percent ultimately die of heart disease or lung cancer, according to McCloskey's team.